Currently it's not possible to research 2 traits on similar items, at the same time. For example. If you have 2 flame staffs, each with a different trait you will see 2 researchable traits under that staff when you go to the research tab. However, the game mechanics do not currently allow you to research both at the same time (granted you have the skill to research more then 1 at a time).
While I'm sure there are arguments in support of this, I for one think there is no reason why it shouldn't be possible. They can add another skill for it and I would spend the points. Sometimes I only have 2 items and I can only research 1 of them because of this limitation. So I end up loosing a day or more with an idle research slot.
What do other crafters think? Should they put this on the roadmap or not?